US1411003A

US1411003A - Sewing machine

Info

Publication number: US1411003A
Application number: US250431A
Authority: US
Inventors: Voe Albert H De
Original assignee: Singer Co
Current assignee: Singer Co
Priority date: 1918-08-19
Filing date: 1918-08-19
Publication date: 1922-03-28
Anticipated expiration: 1939-03-28

Description

A. H. DE VOE. SEWING MACHINE. APPLICATION FILED AUGJS. 1918.

Patented M1228, 1922.

5 SHEETS-SHEET limma.

I ATTORNEY A. H. DE VOE.

SEWING MACHINE. APPLICATION-FILED AUG.l9, 1918. l 541 ,003 Patented Mar. 28, 1922.

5 SHEETSSHEET 2 INVENTOR QM/1MM By V ATTORNEY III Illlill I |I u H WITNESSES A. H. DE VOE. SEWING MACHINE. APPLICATION FILED Aucma. 1918;

wenn@ Mams, 1922..

5 SHEETS-SHEET 3.

INVENTOR WITNESSES A. H. DE VOE.

. SEWING MACHINE.

APPLICATION FILED ALIGAS, 1918.

mm p om If.

A. H. DE VUE.v

SEWING MACHINE.

APPLICATION FILED AUG.I9. I9I8.

Patented Mar. 28, 1922.

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ALBERT ?H. DE VOE, 0F WESTFIELD, NEW JERSEY, ASSIGNOR T0 THE SING U- FACTUBING COMPANY, A CORPORATIGN 0F NEW JERSEY.

SEWING MACHINE.

Lei-reca.,

Application led August 19, 1913.

To all/whom# may concern.'

f Be itl known that l, ALBERT H. Dn Von, a citizen of the United States, residing at Westfield, in the county of Union and State of New Jersey, have invented certain new andvuseful Improvements in Sewing Machines, of which the following is a specification, reference being had therein to the accompanying drawings. r rlhis invention relates primarily to certain new and useful improvements in stitchforming mechanisms for sewing machines and secondarily to improvements in sewing machines of thetype disclosed vinmy Patent No. 858,161 and designed for producing a scalloped edge finish known commercially as shell tucking.

In my prior machine the stitching mechanism produced a single line of stitches and operated in conjunction with a feeding mechanism, the normal feeding action of which was periodically interrupted while a pusher'indented the edge of the work sufficiently to cause the needle to pass down outside of the material and form an overedge stitch serving to bind in or confine the indented edge-portion of the work.

In order to increase the range of usefulness of theI machine, a second needle was added to form a line of stitches disposedY at a greater distance from the edge of the materialthan the first line of stitches as shown in my copending application, Serial No. 166,085, filed May 3, 1917. llt was found, however, that during the eriods of interruption of the normal feedlng action of the machine and while the first-mentioned needle was making the overedge stitch, the second or added needle was making an additional stitch in the same needle puncture, thus forming a knot or ob'ectionable bunching of thread marring the nished product.

The invention has for an object to provide a stitch-forming mechanism which will operate normally to produce one stitch per cycle of operations, and which may be caused to operate abnormally to `prolong the time of formation of a given stitch one orl more cycles beyond the particular cycle in which it would normally have been completed.

Another object of the invention is to prevent or delay the formation o-f a stitch by one of a plurality of needles during a period Specification 'of Letters Patent.

Serial No. 250,431. ,a

of the machine and while another needle is making a displaced stitch. ln other words the invention has for an object, to prolong the time of formation of a stitch by one needle and its complemental loop-taker so that the time of formation of said stitch will be substantially equal to the time required by another needle and its loop-taker to make a plurality of stitches.

The machine being preferably fitted with loopers cooperating with the needles to form chain-stitches, the-inventionhas for a further objectA to interrupt or suspend the normal cooperation of a needle and chainstitch looper during a reciprocation of the needle without losing control of the previous needle-loop detained below the throatplate, whereby when normal stitching is claims.

ln the particular embodiment of the invention shown and described, the machlne is provided with two needles andv two loopers each of the well known rotary type having a loop-taking beak and a loop-deflecting wing of substantially the form disclosed in the patent to Borton No. 525,043; a looper of this type operating to seize a needle-loop andv pass it through a previous needle-loop held distended by the body of the looper, after which the distended needleloop is cast off and drawn up to the work as the new loop is beingrdistended and given a half. twist bythe action of the looper prior to the passage of a new loop through the distendedloop. 1

The machine is equipped with feeding mechanism and-4 automatic means for peri-- odically suspending the normal feeding action thereof, such mechanism and means being preferably constructed substantially in accordance with the disclosure of my said patent. ln order that the needle nearer the edge of the work may form a binding stitch over the edge ,of the work during each period of interruption of the feed, the machine is equipped with a periodically acting pusher movable transversely of the line of feed for indenting the edge of the work at intervals for the assage of the needle beyond the same, an a periodically acting bifurcated auxiliary work-clamping member for securely holding the edge of the vwork during the action ot' the pusher upon an edge-portion intermediate those so held; the pusher and auxiliary work-clamp \functioning substantially in the manner disclosed in my said patent.

\To obviate the periodical formation of two stitches in the same needle-puncture, when the feed is interrupted, such stitches constituting an objectionable knotting or bunching of the stitching thread in the additional row of stitches, means are provided for interrupting the normal cooperation of the addedvneedle with its looper so that the stitch-forming operation of said needle and looper will be held in abeyance during the formation of the overedge stitch by the first needle. To secure this suspension of the normal cooperation of the added needle and its looper without losing control of the last needle-loop held distended by the body of the looper,'means are provided, in the particular embodiment shown and described, for shifting the looper-supporting shaft axially away from the needle to such an extent that the looper-beak will miss the nascent needle-loop and pass outside of the previous needle-loop, thereby reengaging or retaining control of said previous loop during the cycle of suspended stitch-forming actlvity.

As is well known, a rotary looper of the type referred to operates to give a half twist to the nascent needle-loop as it is being distended and spread prior to the passage of a new loop through it. In the present instance, during the idle rotation of the second or added looper, the distended needleloop will be reengaged by the looper just prior to normal cast-off position and detained upon the body of said looper, being merely given anadditional half twist for each idle rotation of the looper prior to resumption of the normal stitching action.

hen normal stitching is resumed a new needle-loop will be seized and passed through this previous loop which has been detained by the looper for a plurality of (in the present instance, two) revolutions of the latter thus keying said previous loop and forming a stitch of normal length and appearance. The additional twist of said detained loop will be scarcely perceptible at the under side of the work and knotting or bunching of the stitching thread each time the feed is. interrupted will be entirely avoided, thus giving the inner row of stitches the uninterrupted and even appearance of ordina ry straightaway stitching.

The invention will be fully understood by reference to the accompanying drawings, in

which Fig. 1 is a side elevation of a machine Fig. 2 is a horiembodying the invention.

zontal section on the line 2-2, Fig. 1, showing the cloth-plate and adjacent mechanism in plan. F 2ZL is a perspective view of the presser footshown in Fig. 2. Fig. 3 is a planl View of the mechanism below the clotli-plate. Fig. 4 illustrates in end elevation a portion of the mechanism for shifting the left-hand looper shown in Fig. 1. Fig. 5 is a vertical section on the line 5 5, Fig. 1. Fig. 6 is a vertical section on the line 6-6, Fig. 3. Fig. 7 is la perspective view of the auxiliary work-clamp and pusher operating means. Fig. 8 is a vertical sect-ion through the axis of pivotal movement of the auxiliary work-clamp. Fig. 9 is a vertical section transversely of the axisof pivotal movement of the auxiliary work-clamp. Fig. 10 shows the needles and loopers in normal cooperative relation. Fig. 11 shows the left-hand -looper shifted to suspend or interrupt its in Fig. 11, and Figs. 13 and 14 are bottomv and top plan Views, respectively, of a sample of work produced by the machine.

In the specific embodiment of the inveiition illustrated, the machine frame comprises the base l, the standard 2, and overlianging bracket-arm 3 terminating in thehead 4 beneath which and above the base 1 is supported the cloth-plate 5. Journaled in the frame below the cloth-plate 5 is the mainshat't 6, the rearward end of which carries a belt-pulley 7 and is formed with a crankextension 8 carrying a balance wheel 1l; the crank being connected to the oscillatory needle-driving shaft 9 bymeans of the pitman 10. The needle-driving shaft 9 is formed at its forward end with a crank 12 connected by means of the link 13 to the reciprocating needle-bar 14 journaled in the head 4 and at its lower end carrying the needle-clamp block 15 in which is secured a pair of eye-pointed needles nl and n2, the former being intended to stitch near the edge of the work and form the periodical overedge stitches serving to bind the edge of the work in scalloped formation while the latter forms a line of straightaway stitches at a greater distance from the edge and is useful, for example, in stitching along the inner edge of a backing strip, as disclosed in my said copending application. Cooperating with the needles 11,1 and n2 to form stitches are the loop-takers t1 and t2, each of which, in the particular embodiment of the invention shown and described` is given the form of a rotary chain-stitch looper of the well known type having a loop-taking beak b and a loop-deliecting wing w; the beak b operating to seize a nascent needle-thread loop and carry it through a previous needle-loop held spread upon the body of the looper, after which the nascent needle-loop is drawn out and then deflected to one side by the wing w while being given a half twist, in a manner well understood, preparatory to being held in spread condition upon the body of the looper for enchainment with the next needle-loop.

The looper t1 is mounted on the forward end of the main-shaft 6 while the looper t2 is mounted upon a shaft 16 journaled for rotary and endwise sliding movements coaxially with the shaft 6 in a bearing bushing 17 fixed/within the upwardly extending bearing lug 18 carried by the laterally extending arm 19 of thefeed-supporting bracket-19 fixed to the base 1. The loopers t1 and t2 are driven at the same speed with their beaks abreast; the looper t2 receiving its motion from the pinion 20 which is fixed to the shaft 6 and meshes with the gear 21 fixed to the rearward end of the counter-shaft 22 to thel forward end of which is fixed the gear 23 meshing with the pinion 24 having its hub 25, Fig. 3, secured to the looper-shaft 16 by v'means of the screw 26. The counter-shaft 22 is journaled in the bearing lugs 22 and 18, the former constituting a forwardly projecting portion of the bracket 19, F ig. 6.

The looper-shaft 16 is mounted for endwise sliding movements in order that the looper t2 may be shifted away from its complemental needle 11,2 and its beak caused to miss the loop presented by said needle and pass outside of the previous needle-loop which is held spread upon the body vof the looper. To this end the looper-shaft 16 has fixed thereto a collar 27 spaced from the hub 25 of the pinion 24 and serving to confine against endwise movementnpon the shaft the enlarged and apertured rearward extremity of a lateral pin 28 the forward reduced extremity of which carries a roll 29 entering a guideway 3 cut in the'rearward face of a block 31 depending from the clothplate 5. l

Journaled upon the lateral pin 28 is the block 32, Figs. l and 4, to which is fixedly secured one end of a link 33, the other end of which is pivotally connected at 34 to the upstanding lever 35-fulcrumed at `36 on the bed 1, and, at its upper end, carrying a ball-pin 37 which is connected by the link 38 with another ball-pin 39 projecting forwardly from the shiftable support 40 for the pusher 41 to be hereinafter more fully described.

The work clamping and indenting mechanism is preferably constructed as follows:

Secured to a plate-like extension 42 at the lower end of the standard 2'is one leg of a frame-member 43 of irregular lll-shape, Fig. 2, disposed mainly between the`clothpla-te 5 and the bracket-arm 3. The framemember 43 is formed with a bearing lug 44 in which is journaled the hollow stud-shaft 45 carrying the gear 46 in the hub 47 of which is cut a peripheral cam-groove 48 having a long dwell-producing portion and a the pusher support 40, the latter including the downwardly projecting bracket-piece 54 horizontally socketed to receive the4 shank of the work-engaging member or pusher 41, as shown in Figs, 1 and 7. rllhe pusher-support 40 further includes a rearward extension terminating in a lateral arm 55 in which is cut a horizontal guideway 56 entered by a guidepin 57 fixed to the U-frame 43. Projecting forwardly from the arm 55 ofthe pusher 40 is a cam-follower roll 58 which enters the cam groove 48. It will thus be seen that once in each five stitch-forming cycles the pusher-support will be shifted toward and from the stitching point as the cam-inclines adjacent the offset 49 act upon the followerl roll 58. This movement of the pusher-support will, through the previously described connections with the ball-pin 39, shift the looper t2 toward and from abnormal position. The pusher 41 consists of a finger-piece having a vertical slot 59 in its forward or workengaging end to embrace the path of the needle nl when said pusher occupies its workengagingv position.

The auxiliary work clamp comprises a shank-portion 60 carried by and fixed to a pin V61 and having at its forward end spaced parallel clamping jaws 62 which are adapted to grip the edge of the work at spaced points disposed respectively in front and in rear of the stitching point. The pin 61 is journaled in the bearing lug 63 depending from the free leg 52 of the U-frame 43 and has fixed to its rearward end a collar 64'. A light spring 65 coiled about the tubular extension 66 ofthe lug 63 and anchored at its opposite ends to the lug 63 and collar 64, respectively, serves to'yieldingly maintain the clamping jaws 62 in raised or ineffective position.

Extending upwardly from the shank portion 60 of the auxiliary work-clamp is an ear 67 to which is fixed the headed pin 68 surrounded by a relativelyV stiff compression spring 69 the inner end of which bears against a lateral ear 7 O formed on the clampclosing lever 71 which is fulcrumed to turn upon and relatively to' the pin 61. rlhe lever 71 is formed with an upwardly and rearwardly extending arm 72 terminating in a face 73 above the level of the axis of the lever 71, Fig.' 1, and resting against the roll 74 carried by the bracket member 54 of the pusher-support. When the pusher is shifted to operative position, the roll 74 delects the arm 72 upwardly thereby tending to compress the spring 69. The spring 69, however, overcomes the spring 65 and iirst presses the clamping feet 62 into grip- 'ping relation with the edge of the workl 4the spring 69 thereafter yielding to permit movement of the roll 74 to a position directly beneath the extremity of the arm 72, thereby increasing the pressure of the clamping feet upon the work. The relation of the face 73 to the axes of the levers 71 and 35 is such that the clamping feet are pressed into gripping engagement With the .Work before the work is indented by the pusher.

The feeding mechanism is substantially the same as that shown and described in my prior Patent No. 858,161, and comprises the usual four-motion feed-dog 75 operating through the apertured throat-plate 76 which is let into the work-supporting plate 5. The feed-dog 75 is fixed to the feed-bai` 77 pivoted at its rear end to the feed-rocker 78, .the latter including the feed rock-shaft 79 which is pivotally mounted upon trunnion-screws 80 fixed in the aperture ears 81 of' the feed-supporting bracket 19. Clamped to the feed rock-shaft 79, isa depending arm 83 the extremity of which is pivotally connected at 84 with the feedactuating lever 85 provided with the yoke 86 intermediate its ends embracing the usual feed-actuating eccentric 87 upon the main-shaft. The forwardly disposed extremity of the lever 85 is provided with a lateral stud 88 entering a guidinggroove 89 in the head of the feed regulating lever 90 pivoted upon the machine frame by means of a suitable fulcrum screw 91 and provided with a finger-piece 92 for shifting the feed-regulating lever to vary the inclination of its guiding groove for correspondingly varying the eective actionv of the feed-actuating eccentric upon the feedrocker in a manner well known.

rl`he feed-bar is pivotally connected to the feed-lifting lever 94 at a point 93 intermediate the ends of the latter. At its forward end the lever 94 is connected to the lowerend of a pitman 95 the upper end of which embraces the feed-lifting-eccentric 96 on the main-shaft 6. rlhe lever 94 is fulcrumed at 97 upon the upper end of the link 98 pivotally supported at the free end of one arm 99 of the feed-interrupting rocker 100 which is journaled upon the feed rock-shaft 79. rThe other arm 101 of the feed-interrupting rocker carries at its free end a follower-roll 102 entering the camgroove 103 cut in the side face of the gear 46. As shown in Fig. 5, the cam-groove 103 is concentric throughout the major portion of its length but is formed with an outwardly disposed offset 104 which depresses the arm 101 of thefeed-interrupting rocker once every ve stitch-forming cycles, and,

through the link 98, Alowers the fulcrum 97 of the feed-lifting lever sufficiently to prevent engagement of the feed-dog with the work during a feed-advancing stroke of the feed-rocker 78. The feed-supporting bracket 19 is grooved or cut away at 99x to aHord clearance for the arm 99 in its downward movement. i

Cooperating with the feed-dog 75 is the spring pressed presser-foot 105 formed with the clearance slots 106 for the gripping feet of the auxiliary work-clamp and with the clearance slot 107 for the pusher 4l. The presser-foot is further formed with a keyhole slot 107 for the needle n2; the needle nl operating at the inner end' of theslot 107.

The machine constituting the specific embodiment of the invention shown and described, is yequipped with strip-folding guides constructed and arranged substantlally in the manner disclosed in my said copending application for presenting an edging stripanda backing strip in assembled relation with the'edge of the body-fabric, as illustrated in said application and in Figs. 13 and 14 of the present case. Suitably supported beneath thecloth-plate is the stripfolding guide 108 adapted to fold upwardly and inwardly the opposite edges of a backing strip 109 and present the folded strip to the needles in the form shownin Figs. 10 and 11; the throat-plate 76 being grooved as shown to receive and guide the folded strip below the level of the pusher 41. Above the strip folding guide 108 and below the cloth--plate is a second strip folding guide 109 shaped to fold an insertion or edging strip 110 centrally and present it to the needle nl as shown in Fig. 10. Disposed above the guide 109 and cloth-plate 5 is an edge-folding guide 111 adapted to turn under the edge of the body-fabric 112 and present it in overlapped relation with the folded

strips

109 and 110.

In the operation of the machine, the bodyfabric 112 and folded

strips

109 and 110 are fed to the needles in substantially the arrangement shown in Fig. 10. After four regular stitches have been formed in the usual manner and just as the needles are startingA to rise, the offset portions 49 and 104 of the respective cam-slots 48 and 103 operate substantially simultaneously to drop the feed to inoperative position so that the next feed-advancing stroke will be ineffective and to cause the auxiliary work-clamp to grip the work while the pusher 41 indents the edge of the work by crowding .the edge of the body-fabric 112. and the folded strip 110 inwardly, as shown in F ig. 11; the pusher missing the backing strip 109 in the same manner as illustrated in my said copending application.

Just asthe pusher reaches its advanced position the needles descend; the needle n1 ll I passing outside of the

indented materials

112 and 110 and entering the backing strip 109 to form the stitch s1, while the needle n2 again enters its last formed puncture in the work.` During the advance of the pusher, the looper t2 is shifted away from the needle n2, Fig. 11, so that, as the needles rise, the beak of looper t2 will miss the nascent loop m2 of needle n2 and will pass outside of the previous loop y2 of said needle or,\in other words, will pass to the same side\of both limbs of said previous needle loop y2, as shown in Figs. 11 and 12. The saidn previous loop ,fz/2 will therefore not be cast off from the looper t2 but will be maintained under control upon thebody of said looper, being merely given an additional half twist as the looper performs its next rotation and while the needle nl and looper t1 are forming the overedge stitch s1.

Thus it will be seen that means have herein been provided for suspending or delaying the completion of a partially formed stitch for a time equal to an additional cycle without interrupting the motions of the stitch-forming instrumentalities or, from another viewpoint, means have been provided in a machine which normally completes one stitch per cycle, for causing the completion of a given partially formed stitch to be delayed an additional cycle.

As soon as the needles reach /the bottom of their stroke, Fig. 11, the feed is restored to normal operating position by the lever` 101 as the cam-roll 102 is lifted into the main concentric portion of the cam-slot103. After the beak of the looper t2 reaches the position shown in Fig. 12, the pusher 47 is returned to inoperative position and with it the looper t2 is restored to normal operative position.

lt is to be understood that the invention in certain aspects is not limited to a machine for producing scalloped tucks or to a machine having a feed which may be periodically interrupted. Nor is the invention limited to chain stitch forming mechanism except where such express limitation appears in claims. r1`he invention being of broad scope, the form and arrangement of the various parts are susceptible of material modification without 'departure from the invention, various substitutions, alterations, and modifications being obvious to those skilled in the art. y

Having thus'set forththe nature of the invention, what li claim herein is 1. ln a sewing machine, the combination with a reciprocating needle and complemental loop-taker operatingnormally to produce one stitch per cycle of operations, of means for delaying the drawing up of a lneedle-loop distended by the loop-taker an additional cycle beyond that during which it Would normally be drawn up.

2. lln a sewing machine, in combination, .a reciprocating needle, a looper operating normally to maintain control of a previous needle-loop while it is being enchained with a nascent needle-loop seized by said looper,

and means for avoiding seizure of a nascent form an idle rotation While maintaining the previous needle-loop under control. v'

4. In a sewing machine, in combination, a

reciprocating needle, a looper operating normally to maintain control of a previous needle-loop while it is being enchained with a nascent needle-loop seized by -said looper,

and means for shifting said looper to `an abnormal operating position wherein it will fail to seize the nascent needle-loop and will maintain control of the previous needle-loop.

5. ln a sewing machine, the. combi-nation with a reciprocating needle and a rotary chain-stitch looper having a loop-seizing beak, of means for shifting said looper laterally of the needle-path to a position such that the looper-beak will miss the nascent needle-loop and pass to the same side of both limbs of the detained needle-loop,

thereby reengaging and maintaining control of said detained needle-loop during the period of suspension of normal cooperation of said needle and looper.

6. ln a. sewing machine, in combination, a reciprocating needle, a rotary looper having a loop-seizing beak and a loop-deecting wing, said looper operating normallyl to seize a needle-loop and carry it through a previous needle-loop detained upon the body of said looper, and automatic means for periodically shifting said looper la'terallyoif the needle-path to a position such that the looper-beak' will miss the nascent needle-loop and pass to the Isame side of both limbs of the detained needle-loop, thereby reengaging and maintaining control ofy said needle-loop during a subsequent rotation. v

7. In a sewing machine, the combination Aof a reciprocating needle and complemental chain-stitch looper, with means for suspending the normal cooperation of said needle and looper while maintaining control of the last needle-loop seized by said looper and without arresting. the movements of said needle and looper.

8. lin a sewing machine, the combination with a plurality of reciprocating needles and their respective complemental loop-takers, of means for shifting the working position of one of said loop-takers away from its respective needle without arresting the movements of said needles and loop-takers, thereby suspending the normal cooperation of one of said needles and its loop-taker during the Aformation of a stitch by another of said 10. ln a sewing machine, in combination.

a reciprocating needle-bar, a plurality of needles mounted on said bar, feeding mechanism, loop-takers cooperatingvwith said needles, and means for producing a relative lateral shift between one of said loop-takers and the needle-bar while another loop-taker is cooperating normally with its complemental needle, thereby producing differential results as to the relative numbers of stitches formed by the said needles.

11. ln a sewing machine, in combination, a reciprocating needle, complemental looptaking means cooperating with said needle to form stitches, feeding mechanism including means for-interrupting the normal feeding action of said mechanism, means for suspending the normal cooperation of the needle and loop-taker without arresting their movements when the normal feed of the material is interrupted, and means for performing an operation upon the work during the period of interruption of the feed.

12. ln a sewing machine, in combination, a reciprocating needle, complemental looptaking means cooperating with said needle to form stitches, feeding mechanisms including automatic means for periodically interrupting the normal feeding action of said mechanism during the continued operation of the machine and automatic means acting to suspend the normal cooperation of said needle and loop-taker when the feed is interrupted.

13. ln a sewing machine, in combination,

for suspending the normal cooperation of another of said needles with its loop-taker when the feed is interrupted.

14. ln a sewing'machine, in combination, a plurality of reciprocating needles, complemental loop-takers, a work-engaging element, and meansconnected with said workengaging element for suspending the normal stitch-forming action of one of 'said needles and its complemental loop-taker during the continued normal operation of another needle and loop-taker- 15. lin a sewing machine, in combination, a reciprocating needle, a complemental looptaker, feeding mechanism, a work-engaging element, and means connected with said work-engaging element for suspending the normal cooperation of said needle and looptaker without arresting their movements.

16. lin a sewing machine, in combination, a frame, a reciprocating needle, a complemental loop-taker, a movable work-engaging clement, and automatic means connected with said work-engaging element for shifting said loop-taker to abnormalv operating position relative to said needle, t-herebyA suspending the stitch-forming action.

17. ln a sewing machine for producing shell-tucking, in combination, a plurality of reciprocating needles, complemental looptakers cooperating with said needles to form stitches, feeding mechanism, means-for periodically interrupting the normal feeding action of said feeding mechanism, a pusher for indenting the edge of the work to cause one of said needles to form an overedge stitch during an interruption of the normal feed of the work, and means for suspending the normal cooperation of another of said needles and its loop-taker while the overedge stitch is being formed.

In testimony whereof, l have signed my name to this specification.

ALBERT H. DE VDE.